New Delhi: It’s a breakthrough that could change the lives of millions. A team of doctors from the country’s premier medical research institute, AIIMS, has broken new grounds in ophthalmology by using a single donated cornea to help three patients recover their vision.
Until now, one donated cornea was required to revive the eyesight of one patient. The latest breakthrough means the wait for cornea donors could go down significantly for the visually-impaired. In a country like India, where eye donation is still not so popular, this spells a ray of hope for lakhs of sightless people.
The AIIMS team used the cornea of a 44-year-old donor, who died of a heart attack, and sliced it to transplant its different parts into the eyes of three different patients in one day — one of them 60 years old, another around 40, and the third a five-year-old boy.
What’s more, follow-up of the three patients showed that there was no rejection — in other words, the surgeries were 100% effective. New tissues had grown over the transplant, while their visual acuity improved greatly in just three months. After successfully testing the surgery on 20 more patients, the team has announced its feat in the latest edition of the journal Archives of Ophthalmology.
The team, led by professor of ophthalmology Dr J S Titiyal, an expert in cornea and refractive surgery, and his former colleague Dr Rasik Vajpayee, now based at the University of Melbourne, sliced the tissue of the cornea into three parts to replace diseased areas of three patients. The 40-year-old-man had a diseased endothelium (deepest part of the cornea responsible for regulating fluid), while the 60-year-old man suffered from a defective corneal strome (thick transparent middle layer). The little boy had a total limbal stem cell deficiency following chemical burns in his right eye.
AIIMS team’s feat could help many
New Delhi: Of the 1.12 crore blind in India, as many as 3 million suffer from corneal problems. And out of this 3 million, 26% are children. It is estimated that India needs 2 lakh donated cornea every year, but gets only 15,000 donors. Out of this 15,000, almost half are not found fit for restoring vision. The team’s feat could, therefore, bring a smile to many.
So far, the practice has been to transplant the entire cornea in every patient, irrespective of which part of her eye was diseased. In the cases where only a part of the donated cornea tissue was transplanted, the rest of the cornea was not utilised.
The AIIMS team decided to get around the problem by seeking to figure out whether the gap could be bridged by using one donated cornea for multiple patients. Dr Titliyal told TOI: ‘‘We decided to see whether we could slice the different parts of the cornea, and use it on different patients, based on their requirement. Our experiment worked.’’
He is particularly pleased over zero-rejection rate. In fact, the team has discovered that transplanting a smaller part of the cornea lowered rejection risk. While corneal transplants have a fairly high success rate — ranging from 30%-75% in India — problems such as rejection of the new cornea are common, requiring a second transplant.
‘‘Chances of the second surgery succeeding usually goes down by 50%. Our latest technique has shown a drop of rejection rate by 95% as the antigenic load on the patient is minimal because only the required part of the donor is being cut and transplanted instead of the entire cornea,’’ said Dr Titiyal.
He explained why all eye donations don’t help in restoring vision. As a rule, the eye has to be removed from the body within six hours of death. If this is not done, the eye quality decreases, particularly so in India because of the warm weather. Also, eyes taken from people who died of diseases like blood cancer, hepatitis B and HIV are not used. The eye removal takes only 10-15 minutes and does not cause any disfigurement, he added.
The waiting list in some eye banks is as much as two years. Ophthalmologists say that less than 1% of those who pledge their eye actually donate them.
